Re: st: RE: marksample

Maarten / Nick,
Thank you for your time / comments.
Ashim.
On Thu, Sep 11, 2008 at 7:28 PM, Maarten buis <maartenbuis@yahoo.co.uk> wrote:
> --- Ashim Kapoor <ashimkapoor@gmail.com> wrote:
>> I am reading mark from the programming manual. I get the idea of
>> st_views. I do not understand what the idea behind mark is. Why is
>> this variable named in a funny way like __0000 ? Is this 0 / 1 in
>> each row depending on some criteria ? What is that criteria?
>
> Often you don't want your program to apply to all observations in your
> data, e.g. you want to ignore rows where at least one of the variable
> you use in your data contains missing values, or want to allow users to
> restrict their analysis to females only.
>
> -mark- is a convenience command: it collects after -syntax- the
> relavant variables and marks out (gives them value 0 on the variable
> `touse') observations with missing values on those. It also looks at
> -in- and -if- restrictions.
>
> It is called __000 (though you should never refer to it that way)
> because it is a temporary variable: it is removed once your program is
> finished. The reason why you should never refer to it that way is that
> it could also be called __001 or something else (depending on whether
> you have defined other temporary variables before that). You should
> refer to it as `touse'.
>
> -- Maarten
>
> -----------------------------------------
> Maarten L. Buis
> Department of Social Research Methodology
> Vrije Universiteit Amsterdam
> Boelelaan 1081
> 1081 HV Amsterdam
> The Netherlands
>
> visiting address:
> Buitenveldertselaan 3 (Metropolitan), room N515
>
> +31 20 5986715
>
> http://home.fsw.vu.nl/m.buis/
> -----------------------------------------
>
>
>
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